Synthetic Insulation
An affordable alternative to down, synthetic insulation is available in many varieties. Advantages of synthetic fill are its ability to maintain insulatingproperties when wet and that it has less required maintenance than down.

Thermolite Quallo
Engineered with seven-hole fibers, Thermolite Quallo provides extraordinary warmth and performance. Seven holes allow the fiber to trap and maintain more warmth than solid fibers. It also maintains its high loft, softness, and insulating properties over time.

Two-layer, offset-quilt construction
By layering two or more sheets of insulation between the liner and shell of a sleeping bag, heat is easily trapped and maintained. To eliminate cold spots, one layer of fill is stitched to the liner, another layer is stitched to the shell, and then the quilt lines are offset so they do not lie on top of one another. Offset quilt construction is durable and maintains its shape and structure after many uses.
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I got this bag for a light bag to use for the spring and fall weather. I found it for $33 on Sierra trading post and felt that it was the best deal that I was going to find. All in am it is a pretty good bag for the price, good warmth, light and good stuff size.